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path: root/drivers/spi/spi-omap2-mcspi.c
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2024-07-15Merge tag 'spi-v6.11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi Pull spi updates from Mark Brown: "There's some quite exciting core work in this release, we've got the beginnings of support for hardware initiated transfers which is itself independently useful for optimising fast paths in existing drivers. We also have a rework of the DMA mapping which allows finer grained decisions about DMA mapping messages and also helps remove some bodges that we'd had. Otherwise it's a fairly quiet release, a few new drivers and features for existing drivers, together with various cleanups and DT binding conversions. One regmap SPI fix made it's way in here too which I should probably have sent as a regmap fix instead. Summary: - Support for pre-optimising messages, reducing the overhead for messages that are repeatedly used (eg, reading the interrupt status from a device). This will also be used for hardware initiated transfers in future. - A reworking of how DMA mapping is done, introducing a new helper and allowing the DMA mapping decision to be done per transfer instead of per message. - Support for Atmel SAMA7D64, Freescale LX2160A DSPI and WCH CH341A" * tag 'spi-v6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (72 commits) spi: dt-bindings: at91: Add sama7d65 compatible string spi: add ch341a usb2spi driver spi: dt-bindings: fsl-dspi: add compatible string 'fsl,lx2160a-dspi' spi: dt-bindings: fsl-dspi: add dmas and dma-names properties spi: spi: Remove unnecessary ‘0’ values from status spi: spi: Remove unnecessary ‘0’ values from rc spi: xcomm: fix coding style spi: xcomm: remove i2c_set_clientdata() spi: xcomm: make use of devm_spi_alloc_host() spi: xcomm: add gpiochip support spi: dt-bindings: snps,dw-apb-ssi.yaml: update compatible property spi: dt-bindings: fsl-dspi: Convert to yaml format spi: fsl-dspi: use common proptery 'spi-cs-setup(hold)-delay-ns' spi: axi-spi-engine: remove platform_set_drvdata() spi: spi-fsl-lpspi: Pass pm_ptr() spi: spi-imx: Pass pm_ptr() spi: spi-fsl-lpspi: Switch to SYSTEM_SLEEP_PM_OPS() spi: spi-imx: Switch to RUNTIME_PM_OPS/SYSTEM_SLEEP_PM_OPS() spi: add EXPORT_SYMBOL_GPL(devm_spi_optimize_message) spi: add devm_spi_optimize_message() helper ...
2024-07-04spi: omap2-mcspi: Revert multi mode supportMark Brown
There have been multiple reports that the multi-mode support in the OMAP2 McSPI driver has caused regressions on existing systems. There's been some discussion and some proposed changes but nothing that's been tested by all the reporters. Drop the patch for v6.10, hopefully we can get to the bottom of the issue and reenable the feature for v6.11. Reported-by: Colin Foster <colin.foster@in-advantage.com> Reported-by: João Paulo Gonçalves <jpaulo.silvagoncalves@gmail.com> Fixes: e64d3b6fc9a3 ("spi: omap2-mcpsi: Enable MULTI-mode in more situations") Signed-off-by: Mark Brown <broonie@kernel.org> Link: https://patch.msgid.link/20240704-spi-revert-omap2-multi-v1-1-69357ef13fdc@kernel.org Signed-off-by: Mark Brown <broonie@kernel.org>
2024-06-11spi: Rework DMA mapped flagMark Brown
Merge series from Andy Shevchenko <andriy.shevchenko@linux.intel.com>: The first part of the series (patches 1 to 7) is an introduction of a new helper followed by the user conversion. This consolidates the same code and also makes patch 8 (last one) be localised to the SPI core part. The last patch is the main rework to get rid of a recently introduced hack with a dummy SG list and move to the transfer-based DMA mapped flag. That said, the patches 1 to 7 may be applied right away since they have no functional change intended, while the last one needs more testing and reviewing.
2024-06-10spi: add missing MODULE_DESCRIPTION() macrosJeff Johnson
make allmodconfig && make W=1 C=1 reports: WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/spi/spi-altera-core.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/spi/spi-fsl-lib.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/spi/spi-omap2-mcspi.o WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/spi/spi-qup.o Add the missing invocations of the MODULE_DESCRIPTION() macro. Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com> Link: https://lore.kernel.org/r/20240609-md-drivers-spi-v1-1-1c7444f53cde@quicinc.com Signed-off-by: Mark Brown <broonie@kernel.org>
2024-06-10spi: omap2-mcspi: Use new spi_xfer_is_dma_mapped() helperAndy Shevchenko
Replace a few lines of code by calling a spi_xfer_is_dma_mapped() helper. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on SM8650-QRD Link: https://lore.kernel.org/r/20240531194723.1761567-5-andriy.shevchenko@linux.intel.com Reviewed-by: Serge Semin <fancer.lancer@gmail.com> Tested-by: Nícolas F. R. A. Prado <nfraprado@collabora.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2024-03-28spi: omap2-mcpsi: Enable MULTI-mode in more situationsLouis Chauvet
Enable multimode when a transfer of multiple small words can be transformed in a transfer with a single bigger word. This is allowed as long as the result on the cable is the same, so word_delay must be zero. Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com> Link: https://msgid.link/r/20240327-spi-omap2-mcspi-multi-mode-v3-3-c4ac329dd5a2@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
2024-03-28spi: omap2-mcspi: Add support for MULTI-modeLouis Chauvet
Introduce support for MULTI-mode in the OMAP2 MCSPI driver. Currently, the driver always uses SINGLE mode to handle the chip select (CS). With this enhancement, MULTI-mode is enabled for specific messages, allowing for a shorter delay between CS enable and the message (some FPGA devices are sensitive to this delay). The OMAP2 MCSPI device can use two different mode to send messages, SINGLE and MULTI: In SINGLE mode, the controller only leverages one single FIFO, and the host system has to manually select the CS it wants to enable. In MULTI mode, each CS is bound to a FIFO, the host system then writes the data to the relevant FIFO, as the hardware will take care of the CS The drawback of multi-mode is that it's not possible to keep the CS enabled between each words. Therefore, this patch enables multi-mode only for specific messages: the spi_message must contain only spi_transfer of 1 word (of any size) with cs_change enabled. A new member is introduced in the omap2_mcspi structure to keep track of the current used mode. Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com> Link: https://msgid.link/r/20240327-spi-omap2-mcspi-multi-mode-v3-2-c4ac329dd5a2@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
2024-03-28spi: spi-omap2-mcspi.c: revert "Toggle CS after each word"Louis Chauvet
Commit 5cbc7ca987fb ("spi: spi-omap2-mcspi.c: Toggle CS after each word") introduced the toggling of CS after each word for the omap2-mcspi controller. The implementation is not respectful of the actual spi_message content, so the CS can be raised after each word even if the transfer structure asks to keep the CS active for the whole operation. As it is not used anyway in the current Linux tree, it can be safely removed. Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com> Link: https://msgid.link/r/20240327-spi-omap2-mcspi-multi-mode-v3-1-c4ac329dd5a2@bootlin.com Signed-off-by: Mark Brown <broonie@kernel.org>
2024-02-12spi: omap2-mcspi: Revert FIFO support without DMAVaishnav Achath
MCSPI controller have few limitations regarding the transaction size when the FIFO buffer is enabled and the WCNT feature is used to find the end of word, in this case if WCNT is not a multiple of the FIFO Almost Empty Level (AEL), then the FIFO empty event is not generated correctly. In addition to this limitation, few other unknown sequence of events that causes the FIFO empty status to not reflect the exact status were found when FIFO is being used without DMA enabled during extended testing in AM65x platform. Till the exact root cause is found and fixed, revert the FIFO support without DMA. See J721E Technical Reference Manual (SPRUI1C), section 12.1.5 for further details: http://www.ti.com/lit/pdf/spruil1 This reverts commit 75223bbea840e ("spi: omap2-mcspi: Add FIFO support without DMA") Signed-off-by: Vaishnav Achath <vaishnav.a@ti.com> Link: https://msgid.link/r/20240212120049.438495-1-vaishnav.a@ti.com Signed-off-by: Mark Brown <broonie@kernel.org>
2023-10-23spi: omap2-mcspi: Add FIFO support without DMAVaishnav Achath
Currently, the built-in 64-byte FIFO on the MCSPI controller is not enabled in PIO mode and is used only when DMA is enabled. Enable the FIFO in PIO mode by default for transactions larger than the FIFO depth and fallback only if FIFO is not available. When DMA is not enabled, it is efficient to enable the RX FIFO almost full and TX FIFO almost empty events after each FIFO fill instead of each word. Update omap2_mcspi_set_fifo() to enable the events accordingly and also rely on OMAP2_MCSPI_CHSTAT_RXS for the last transfer instead of the FIFO events to handle the case when the transfer size is not a multiple of FIFO depth. See J721E Technical Reference Manual (SPRUI1C), section 12.1.5 for further details: http://www.ti.com/lit/pdf/spruil1 Signed-off-by: Vaishnav Achath <vaishnav.a@ti.com> Link: https://lore.kernel.org/r/20231013092629.19005-1-vaishnav.a@ti.com Signed-off-by: Mark Brown <broonie@kernel.org>
2023-09-26spi: omap2-mcspi: Fix hardcoded reference clockVaishnav Achath
A hardcoded reference clock of 48 MHz is used to calculate the clock divisor values, but the reference clock frequency can be different across devices and can be configured which can cause a mismatch between the reported frequency and actual SPI clock frequency observed. Fix this by fetching the clock rate from the clock provider and falling back to hardcoded reference only if the clock is not supplied. Fixes: 2cd7d393f461 ("arm64: dts: ti: k3-am654: Add McSPI DT nodes") Signed-off-by: Vaishnav Achath <vaishnav.a@ti.com> Reviewed-by: Dhruva Gole <d-gole@ti.com> Link: https://lore.kernel.org/r/20230926113812.30692-1-vaishnav.a@ti.com Signed-off-by: Mark Brown <broonie@kernel.org>
2023-09-11spi: omap2-mcspi: switch to use modern nameYang Yingliang
Change legacy name master/slave to modern name host/target or controller. No functional changed. Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20230823033003.3407403-22-yangyingliang@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org>
2023-08-07spi: omap2-mcspi: remove redundant dev_err_probe()Zhu Wang
When platform_get_irq() is called, the error message has been printed, so it need not to call dev_err_probe() to print error, we remove the redundant platform_get_irq(). Signed-off-by: Zhu Wang <wangzhu9@huawei.com> Link: https://lore.kernel.org/r/20230801135442.255604-1-wangzhu9@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org>
2023-03-27spi: omap2-mcspi: Use devm_platform_get_and_ioremap_resource()Yang Li
According to commit 890cc39a8799 ("drivers: provide devm_platform_get_and_ioremap_resource()"), convert platform_get_resource(), devm_ioremap_resource() to a single call to devm_platform_get_and_ioremap_resource(), as this is exactly what this function does. Signed-off-by: Yang Li <yang.lee@linux.alibaba.com> Reviewed-by: Dhruva Gole <d-gole@ti.com> Link: https://lore.kernel.org/r/20230327055346.76625-1-yang.lee@linux.alibaba.com Signed-off-by: Mark Brown <broonie@kernel.org>
2023-03-11Add support for stacked/parallel memoriesMark Brown
Merge series from Amit Kumar Mahapatra <amit.kumar-mahapatra@amd.com>: This patch is in the continuation to the discussions which happened on 'commit f89504300e94 ("spi: Stacked/parallel memories bindings")' for adding dt-binding support for stacked/parallel memories. This patch series updated the spi-nor, spi core and the spi drivers to add stacked and parallel memories support. The first patch https://lore.kernel.org/all/20230119185342.2093323-1-amit.kumar-mahapatra@amd.com/ of the previous series got applied to https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next But the rest of the patches in the series did not get applied due to merge conflict, so send the remaining patches in the series after rebasing it on top of for-next branch. --- BRANCH: for-next Changes in v6: - Rebased on top of latest v6.3-rc1 and fixed merge conflicts in spi-mpc512x-psc.c, sfdp.c, spansion.c files and removed spi-omap-100k.c. - Updated spi_dev_check( ) to reject new devices if any one of the chipselect is used by another device. Changes in v5: - Rebased the patches on top of v6.3-rc1 and fixed the merge conflicts. - Fixed compilation warnings in spi-sh-msiof.c with shmobile_defconfig Changes in v4: - Fixed build error in spi-pl022.c file - reported by Mark. - Fixed build error in spi-sn-f-ospi.c file. - Added Reviewed-by: Serge Semin <fancer.lancer@gmail.com> tag. - Added two more patches to replace spi->chip_select with API calls in mpc832x_rdb.c & cs35l41_hda_spi.c files. Changes in v3: - Rebased the patches on top of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next - Added a patch to convert spi_nor_otp_region_len(nor) & spi_nor_otp_n_regions(nor) macros into inline functions - Added Reviewed-by & Acked-by tags Changes in v2: - Rebased the patches on top of v6.2-rc1 - Created separate patch to add get & set APIs for spi->chip_select & spi->cs_gpiod, and replaced all spi->chip_select and spi->cs_gpiod references with the API calls. - Created separate patch to add get & set APIs for nor->params. --- Amit Kumar Mahapatra (15): spi: Replace all spi->chip_select and spi->cs_gpiod references with function call net: Replace all spi->chip_select and spi->cs_gpiod references with function call iio: imu: Replace all spi->chip_select and spi->cs_gpiod references with function call mtd: devices: Replace all spi->chip_select and spi->cs_gpiod references with function call staging: Replace all spi->chip_select and spi->cs_gpiod references with function call platform/x86: serial-multi-instantiate: Replace all spi->chip_select and spi->cs_gpiod references with function call powerpc/83xx/mpc832x_rdb: Replace all spi->chip_select references with function call ALSA: hda: cs35l41: Replace all spi->chip_select references with function call spi: Add stacked and parallel memories support in SPI core mtd: spi-nor: Convert macros with inline functions mtd: spi-nor: Add APIs to set/get nor->params mtd: spi-nor: Add stacked memories support in spi-nor spi: spi-zynqmp-gqspi: Add stacked memories support in GQSPI driver mtd: spi-nor: Add parallel memories support in spi-nor spi: spi-zynqmp-gqspi: Add parallel memories support in GQSPI driver arch/powerpc/platforms/83xx/mpc832x_rdb.c | 2 +- drivers/iio/imu/adis16400.c | 2 +- drivers/mtd/devices/mtd_dataflash.c | 2 +- drivers/mtd/spi-nor/atmel.c | 17 +- drivers/mtd/spi-nor/core.c | 665 +++++++++++++++--- drivers/mtd/spi-nor/core.h | 8 + drivers/mtd/spi-nor/debugfs.c | 4 +- drivers/mtd/spi-nor/gigadevice.c | 4 +- drivers/mtd/spi-nor/issi.c | 11 +- drivers/mtd/spi-nor/macronix.c | 6 +- drivers/mtd/spi-nor/micron-st.c | 39 +- drivers/mtd/spi-nor/otp.c | 48 +- drivers/mtd/spi-nor/sfdp.c | 29 +- drivers/mtd/spi-nor/spansion.c | 50 +- drivers/mtd/spi-nor/sst.c | 7 +- drivers/mtd/spi-nor/swp.c | 22 +- drivers/mtd/spi-nor/winbond.c | 10 +- drivers/mtd/spi-nor/xilinx.c | 18 +- drivers/net/ethernet/adi/adin1110.c | 2 +- drivers/net/ethernet/asix/ax88796c_main.c | 2 +- drivers/net/ethernet/davicom/dm9051.c | 2 +- drivers/net/ethernet/qualcomm/qca_debug.c | 2 +- drivers/net/ieee802154/ca8210.c | 2 +- drivers/net/wan/slic_ds26522.c | 2 +- .../net/wireless/marvell/libertas/if_spi.c | 2 +- drivers/net/wireless/silabs/wfx/bus_spi.c | 2 +- drivers/net/wireless/st/cw1200/cw1200_spi.c | 2 +- .../platform/x86/serial-multi-instantiate.c | 3 +- drivers/spi/spi-altera-core.c | 2 +- drivers/spi/spi-amd.c | 4 +- drivers/spi/spi-ar934x.c | 2 +- drivers/spi/spi-armada-3700.c | 4 +- drivers/spi/spi-aspeed-smc.c | 13 +- drivers/spi/spi-at91-usart.c | 2 +- drivers/spi/spi-ath79.c | 4 +- drivers/spi/spi-atmel.c | 26 +- drivers/spi/spi-au1550.c | 4 +- drivers/spi/spi-axi-spi-engine.c | 2 +- drivers/spi/spi-bcm-qspi.c | 10 +- drivers/spi/spi-bcm2835.c | 19 +- drivers/spi/spi-bcm2835aux.c | 4 +- drivers/spi/spi-bcm63xx-hsspi.c | 30 +- drivers/spi/spi-bcm63xx.c | 2 +- drivers/spi/spi-bcmbca-hsspi.c | 30 +- drivers/spi/spi-cadence-quadspi.c | 5 +- drivers/spi/spi-cadence-xspi.c | 4 +- drivers/spi/spi-cadence.c | 4 +- drivers/spi/spi-cavium.c | 8 +- drivers/spi/spi-coldfire-qspi.c | 8 +- drivers/spi/spi-davinci.c | 18 +- drivers/spi/spi-dln2.c | 6 +- drivers/spi/spi-dw-core.c | 2 +- drivers/spi/spi-dw-mmio.c | 4 +- drivers/spi/spi-falcon.c | 2 +- drivers/spi/spi-fsi.c | 2 +- drivers/spi/spi-fsl-dspi.c | 16 +- drivers/spi/spi-fsl-espi.c | 6 +- drivers/spi/spi-fsl-lpspi.c | 2 +- drivers/spi/spi-fsl-qspi.c | 6 +- drivers/spi/spi-fsl-spi.c | 2 +- drivers/spi/spi-geni-qcom.c | 6 +- drivers/spi/spi-gpio.c | 4 +- drivers/spi/spi-gxp.c | 4 +- drivers/spi/spi-hisi-sfc-v3xx.c | 2 +- drivers/spi/spi-img-spfi.c | 14 +- drivers/spi/spi-imx.c | 30 +- drivers/spi/spi-ingenic.c | 4 +- drivers/spi/spi-intel.c | 2 +- drivers/spi/spi-jcore.c | 4 +- drivers/spi/spi-lantiq-ssc.c | 6 +- drivers/spi/spi-mem.c | 4 +- drivers/spi/spi-meson-spicc.c | 2 +- drivers/spi/spi-microchip-core.c | 6 +- drivers/spi/spi-mpc512x-psc.c | 8 +- drivers/spi/spi-mpc52xx.c | 2 +- drivers/spi/spi-mt65xx.c | 6 +- drivers/spi/spi-mt7621.c | 2 +- drivers/spi/spi-mux.c | 8 +- drivers/spi/spi-mxic.c | 10 +- drivers/spi/spi-mxs.c | 2 +- drivers/spi/spi-npcm-fiu.c | 20 +- drivers/spi/spi-nxp-fspi.c | 10 +- drivers/spi/spi-omap-uwire.c | 8 +- drivers/spi/spi-omap2-mcspi.c | 24 +- drivers/spi/spi-orion.c | 4 +- drivers/spi/spi-pci1xxxx.c | 4 +- drivers/spi/spi-pic32-sqi.c | 2 +- drivers/spi/spi-pic32.c | 4 +- drivers/spi/spi-pl022.c | 4 +- drivers/spi/spi-pxa2xx.c | 6 +- drivers/spi/spi-qcom-qspi.c | 2 +- drivers/spi/spi-rb4xx.c | 2 +- drivers/spi/spi-rockchip-sfc.c | 2 +- drivers/spi/spi-rockchip.c | 26 +- drivers/spi/spi-rspi.c | 10 +- drivers/spi/spi-s3c64xx.c | 2 +- drivers/spi/spi-sc18is602.c | 4 +- drivers/spi/spi-sh-msiof.c | 6 +- drivers/spi/spi-sh-sci.c | 2 +- drivers/spi/spi-sifive.c | 6 +- drivers/spi/spi-sn-f-ospi.c | 2 +- drivers/spi/spi-st-ssc4.c | 2 +- drivers/spi/spi-stm32-qspi.c | 12 +- drivers/spi/spi-sun4i.c | 2 +- drivers/spi/spi-sun6i.c | 2 +- drivers/spi/spi-synquacer.c | 6 +- drivers/spi/spi-tegra114.c | 28 +- drivers/spi/spi-tegra20-sflash.c | 2 +- drivers/spi/spi-tegra20-slink.c | 6 +- drivers/spi/spi-tegra210-quad.c | 8 +- drivers/spi/spi-ti-qspi.c | 16 +- drivers/spi/spi-topcliff-pch.c | 4 +- drivers/spi/spi-wpcm-fiu.c | 12 +- drivers/spi/spi-xcomm.c | 2 +- drivers/spi/spi-xilinx.c | 6 +- drivers/spi/spi-xlp.c | 4 +- drivers/spi/spi-zynq-qspi.c | 2 +- drivers/spi/spi-zynqmp-gqspi.c | 58 +- drivers/spi/spi.c | 225 ++++-- drivers/spi/spidev.c | 6 +- drivers/staging/fbtft/fbtft-core.c | 2 +- drivers/staging/greybus/spilib.c | 2 +- include/linux/mtd/spi-nor.h | 18 +- include/linux/spi/spi.h | 34 +- include/trace/events/spi.h | 10 +- sound/pci/hda/cs35l41_hda_spi.c | 2 +- 126 files changed, 1350 insertions(+), 615 deletions(-) -- 2.25.1
2023-03-11spi: Replace all spi->chip_select and spi->cs_gpiod references with function ↵Amit Kumar Mahapatra via Alsa-devel
call Supporting multi-cs in spi drivers would require the chip_select & cs_gpiod members of struct spi_device to be an array. But changing the type of these members to array would break the spi driver functionality. To make the transition smoother introduced four new APIs to get/set the spi->chip_select & spi->cs_gpiod and replaced all spi->chip_select and spi->cs_gpiod references with get or set API calls. While adding multi-cs support in further patches the chip_select & cs_gpiod members of the spi_device structure would be converted to arrays & the "idx" parameter of the APIs would be used as array index i.e., spi->chip_select[idx] & spi->cs_gpiod[idx] respectively. Signed-off-by: Amit Kumar Mahapatra <amit.kumar-mahapatra@amd.com> Acked-by: Heiko Stuebner <heiko@sntech.de> # Rockchip drivers Reviewed-by: Michal Simek <michal.simek@amd.com> Reviewed-by: Cédric Le Goater <clg@kaod.org> # Aspeed driver Reviewed-by: Dhruva Gole <d-gole@ti.com> # SPI Cadence QSPI Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com> # spi-stm32-qspi Acked-by: William Zhang <william.zhang@broadcom.com> # bcm63xx-hsspi driver Reviewed-by: Serge Semin <fancer.lancer@gmail.com> # DW SSI part Link: https://lore.kernel.org/r/167847070432.26.15076794204368669839@mailman-core.alsa-project.org Signed-off-by: Mark Brown <broonie@kernel.org>
2023-03-11spi: omap2-mcspi: Use of_property_read_bool() for boolean propertiesRob Herring
It is preferred to use typed property access functions (i.e. of_property_read_<type> functions) rather than low-level of_get_property/of_find_property functions for reading properties. Convert reading boolean properties to to of_property_read_bool(). Signed-off-by: Rob Herring <robh@kernel.org> Link: https://lore.kernel.org/r/20230310144736.1547110-1-robh@kernel.org Signed-off-by: Mark Brown <broonie@kernel.org>
2023-03-06spi: omap2-mcspi: Convert to platform remove callback returning voidUwe Kleine-König
The .remove() callback for a platform driver returns an int which makes many driver authors wrongly assume it's possible to do error handling by returning an error code. However the value returned is (mostly) ignored and this typically results in resource leaks. To improve here there is a quest to make the remove callback return void. In the first step of this quest all drivers are converted to .remove_new() which already returns void. Trivially convert this driver from always returning zero in the remove callback to the void returning variant. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20230303172041.2103336-51-u.kleine-koenig@pengutronix.de Signed-off-by: Mark Brown <broonie@kernel.org>
2022-09-21spi: omap2-mcspi: Fix probe so driver works againDan Carpenter
This condition was accidentally changed from "if (status < 0)" to "if (status)". The platform_get_irq() function returns non-zero positive values on success so, unfortunately, the driver could not be used. Change the condition back to how it was. Fixes: f4ca8c88c2c7 ("spi: omap2-mcspi: Switch to use dev_err_probe() helper") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/Yyq8Q/kd301wVzg8@kili Signed-off-by: Mark Brown <broonie@kernel.org>
2022-09-19spi: omap2-mcspi: Switch to use dev_err_probe() helperYang Yingliang
In the probe path, dev_err() can be replace with dev_err_probe() which will check if error code is -EPROBE_DEFER and prints the error name. Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20220917122504.1896302-1-yangyingliang@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org>
2022-05-04spi: omap2-mcspi: add support for interword delayAndrea Zanotti
The module omap2-mcspi does not support the interword delay parameter present in the spi transfer. On one side, if the module is instructed to use the dma, this parameter is correctly ignored. However, without the usage of the dma, that parameter should be used. The patch introduce the handling of such delay in the omap2-mcspi module, using standard spi_delay struct. The patch has been tested using as benchmark a DM3730. The delay function used (spi_delay_exec) is already present in the kernel and it checks on its own the validity of the input, as such, no additional checks are present. The range of usage of the udelay function is incremented to 200 us, as the change from udelay to usleep_range introduces not neglectible delays. Signed-off-by: Andrea Zanotti <andreazanottifo@gmail.com> Link: https://lore.kernel.org/r/20220502111300.24754-1-andreazanottifo@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
2022-04-25spi: spi-omap2-mcspi: using pm_runtime_resume_and_get instead of ↵Minghao Chi
pm_runtime_get_sync Using pm_runtime_resume_and_get() to replace pm_runtime_get_sync and pm_runtime_put_noidle. This change is just to simplify the code, no actual functional changes. Reported-by: Zeal Robot <zealci@zte.com.cn> Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn> Link: https://lore.kernel.org/r/20220414085433.2541670-1-chi.minghao@zte.com.cn Signed-off-by: Mark Brown <broonie@kernel.org>
2021-06-01Merge branch 'for-5.13' of ↵Mark Brown
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-5.14
2021-06-01spi: Cleanup on failure of initial setupLukas Wunner
Commit c7299fea6769 ("spi: Fix spi device unregister flow") changed the SPI core's behavior if the ->setup() hook returns an error upon adding an spi_device: Before, the ->cleanup() hook was invoked to free any allocations that were made by ->setup(). With the commit, that's no longer the case, so the ->setup() hook is expected to free the allocations itself. I've identified 5 drivers which depend on the old behavior and am fixing them up hereinafter: spi-bitbang.c spi-fsl-spi.c spi-omap-uwire.c spi-omap2-mcspi.c spi-pxa2xx.c Importantly, ->setup() is not only invoked on spi_device *addition*: It may subsequently be called to *change* SPI parameters. If changing these SPI parameters fails, freeing memory allocations would be wrong. That should only be done if the spi_device is finally destroyed. I am therefore using a bool "initial_setup" in 4 of the affected drivers to differentiate between the invocation on *adding* the spi_device and any subsequent invocations: spi-bitbang.c spi-fsl-spi.c spi-omap-uwire.c spi-omap2-mcspi.c In spi-pxa2xx.c, it seems the ->setup() hook can only fail on spi_device addition, not any subsequent calls. It therefore doesn't need the bool. It's worth noting that 5 other drivers already perform a cleanup if the ->setup() hook fails. Before c7299fea6769, they caused a double-free if ->setup() failed on spi_device addition. Since the commit, they're fine. These drivers are: spi-mpc512x-psc.c spi-pl022.c spi-s3c64xx.c spi-st-ssc4.c spi-tegra114.c (spi-pxa2xx.c also already performs a cleanup, but only in one of several error paths.) Fixes: c7299fea6769 ("spi: Fix spi device unregister flow") Signed-off-by: Lukas Wunner <lukas@wunner.de> Cc: Saravana Kannan <saravanak@google.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> # pxa2xx Link: https://lore.kernel.org/r/f76a0599469f265b69c371538794101fa37b5536.1622149321.git.lukas@wunner.de Signed-off-by: Mark Brown <broonie@kernel.org>
2021-05-20Merge series "drivers: spi - add parenthesis for sizeof" from Zhiqi Song ↵Mark Brown
<songzhiqi1@huawei.com>: This patchset fixes missing parentheses of sizeof reported by checkpatch.pl under drivers/spi/. Zhiqi Song (7): spi: lm70llp: add parenthesis for sizeof spi: mpc512x-psc: add parenthesis for sizeof spi: mpc52xx: add parenthesis for sizeof spi: mpc52xx-psc: add parenthesis for sizeof spi: omap2-mcspi: add parenthesis for sizeof spi: omap-uwire: add parenthesis for sizeof spi: ppc4xx: add parenthesis for sizeof drivers/spi/spi-lm70llp.c | 2 +- drivers/spi/spi-mpc512x-psc.c | 4 ++-- drivers/spi/spi-mpc52xx-psc.c | 4 ++-- drivers/spi/spi-mpc52xx.c | 2 +- drivers/spi/spi-omap-uwire.c | 2 +- drivers/spi/spi-omap2-mcspi.c | 2 +- drivers/spi/spi-ppc4xx.c | 4 ++-- 7 files changed, 10 insertions(+), 10 deletions(-) -- 2.7.4
2021-05-20spi: omap2-mcspi: add parenthesis for sizeofZhiqi Song
Fix missing parenthesis of sizeof reported by checkpatch.pl: WARNING: sizeof *pp should be sizeof(*pp). The kernel coding style suggests thinking of sizeof as a function and add parenthesis. Signed-off-by: Zhiqi Song <songzhiqi1@huawei.com> Link: https://lore.kernel.org/r/1621301902-64158-6-git-send-email-songzhiqi1@huawei.com Signed-off-by: Mark Brown <broonie@kernel.org>
2021-05-20spi: fix some invalid char occurrencesMauro Carvalho Chehab
One of the author names got an invalid char, probably due to a bad charset conversion, being replaced by the REPLACEMENT CHARACTER U+fffd ('�'). Use the author's e-mail has the characters without accents, as also used at the .mailmap file. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/ff8d296e1fdcc4f1c6df94434a5720bcedcd0ecf.1621412009.git.mchehab+huawei@kernel.org Signed-off-by: Mark Brown <broonie@kernel.org>
2021-03-10spi: omap2-mcspi: Activate pinctrl idle state during runtime suspendAlexander Sverdlin
Set the (optional) idle pinctrl state during runtime suspend. This is the same schema used in PL022 driver and can help with HW designs sharing the SPI lines for different purposes. Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com> Link: https://lore.kernel.org/r/20210222023243.491432-1-alexander.sverdlin@gmail.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-09-22spi: omap2-mcspi: Improve performance waiting for CHSTATAswath Govindraju
This reverts commit 13d515c796 (spi: omap2-mcspi: Switch to readl_poll_timeout()). The amount of time spent polling for the MCSPI_CHSTAT bits to be set on AM335x-icev2 platform is less than 1us (about 0.6us) in most cases, with or without using DMA. So, in most cases the function need not sleep. Also, setting the sleep_usecs to zero would not be optimal here because ktime_add_us() used in readl_poll_timeout() is slower compared to the direct addition used after the revert. So, it is sub-optimal to use readl_poll_timeout in this case. When DMA is not enabled, this revert results in an increase of about 27% in throughput and decrease of about 20% in CPU usage. However, the CPU usage and throughput are almost the same when used with DMA. Therefore, fix this by reverting the commit which switched to using readl_poll_timeout(). Fixes: 13d515c796ad ("spi: omap2-mcspi: Switch to readl_poll_timeout()") Signed-off-by: Aswath Govindraju <a-govindraju@ti.com> Link: https://lore.kernel.org/r/20200910122624.8769-1-a-govindraju@ti.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-06-29spi: omap2-mcspi: Convert to use GPIO descriptorsLinus Walleij
The OMAP2 MCSPI has some kind of half-baked GPIO CS support: it includes code like this: if (gpio_is_valid(spi->cs_gpio)) { ret = gpio_request(spi->cs_gpio, dev_name(&spi->dev)); (...) But it doesn't parse the "cs-gpios" attribute in the device tree to count the number of GPIOs or pick out the GPIO numbers and put these in the SPI master's .cs_gpios property. We complete the implementation of supporting CS GPIOs from the device tree and switch it over to use the SPI core for this. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Tony Lindgren <tony@atomide.com> Link: https://lore.kernel.org/r/20200625231257.280615-1-linus.walleij@linaro.org Signed-off-by: Mark Brown <broonie@kernel.org>
2020-02-06spi: spi-omap2-mcspi: Support probe deferral for DMA channelsVignesh Raghavendra
dma_request_channel() can return -EPROBE_DEFER, if DMA driver is not ready. Currently driver just falls back to PIO mode on probe deferral. Fix this by requesting all required channels during probe and propagating EPROBE_DEFER error code. Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com> Link: https://lore.kernel.org/r/20200204124816.16735-3-vigneshr@ti.com Signed-off-by: Mark Brown <broonie@kernel.org>
2020-02-06spi: spi-omap2-mcspi: Handle DMA size restriction on AM65xVignesh Raghavendra
On AM654, McSPI can only support 4K - 1 bytes per transfer when DMA is enabled. Therefore populate master->max_transfer_size callback to inform client drivers of this restriction when DMA channels are available. Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com> Link: https://lore.kernel.org/r/20200204124816.16735-2-vigneshr@ti.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-11-11spi: omap2-mcspi: Remove redundant checksVignesh Raghavendra
Both omap2_mcspi_tx_dma() and omap2_mcspi_rx_dma() are only called from omap2_mcspi_txrx_dma() and omap2_mcspi_txrx_dma() is always called after making sure that mcspi_dma->dma_rx and mcspi_dma->dma_tx are not NULL (see omap2_mcspi_transfer_one()). Therefore remove redundant NULL checks for omap2_mcspi->dma_tx and omap2_mcspi->dma_rx pointers in omap2_mcspi_tx_dma() and omap2_mcspi_rx_dma() respectively. Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com> Link: https://lore.kernel.org/r/20191109041827.26934-1-vigneshr@ti.com Signed-off-by: Mark Brown <broonie@kernel.org>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157Thomas Gleixner
Based on 3 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version [author] [graeme] [gregory] [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema] [hk] [hemahk]@[ti] [com] this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1105 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-15spi: omap2-mcspi: Fix DMA and FIFO event trigger size mismatchVignesh R
Commit b682cffa3ac6 ("spi: omap2-mcspi: Set FIFO DMA trigger level to word length") broke SPI transfers where bits_per_word != 8. This is because of mimsatch between McSPI FIFO level event trigger size (SPI word length) and DMA request size(word length * maxburst). This leads to data corruption, lockup and errors like: spi1.0: EOW timed out Fix this by setting DMA maxburst size to 1 so that McSPI FIFO level event trigger size matches DMA request size. Fixes: b682cffa3ac6 ("spi: omap2-mcspi: Set FIFO DMA trigger level to word length") Cc: stable@vger.kernel.org Reported-by: David Lechner <david@lechnology.com> Tested-by: David Lechner <david@lechnology.com> Signed-off-by: Vignesh R <vigneshr@ti.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-11-15spi: omap2-mcspi: Add missing suspend and resume callsTony Lindgren
I've been wondering still about omap2-mcspi related suspend and resume flakeyness and looks like we're missing calls to spi_master_suspend() and spi_master_resume(). Adding those and using pm_runtime_force_suspend() and pm_runtime_force_resume() makes things work for suspend and resume and allows us to stop using noirq suspend and resume. And while at it, let's use SET_SYSTEM_SLEEP_PM_OPS to simplify things further. Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-10-19spi: omap2-mcspi: Add slave mode supportVignesh R
Add support to use McSPI controller as SPI slave. In slave mode, DMA TX completion does not mean entire data has been shifted out as data might still be stuck in FIFO waiting for master to clock the bus. Therefore, add an IRQ handler for slave mode to know when entire data in FIFO has been shifted out. Signed-off-by: Vignesh R <vigneshr@ti.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-10-19spi: omap2-mcspi: Set FIFO DMA trigger level to word lengthVignesh R
McSPI has 32 byte FIFO in Transmit-Receive mode. Current code tries to configuration FIFO watermark level for DMA trigger to be GCD of transfer length and max FIFO size which would mean trigger level may be set to 32 for transmit-receive mode if length is aligned. This does not work in case of SPI slave mode where FIFO always needs to have data ready whenever master starts the clock. With DMA trigger size of 32 there will be a small window during slave TX where DMA is still putting data into FIFO but master would have started clock for next byte, resulting in shifting out of stale data. Similarly, on Slave RX side there may be RX FIFO overflow Fix this by setting FIFO watermark for DMA trigger to word length. This means DMA is triggered as soon as FIFO has space for word length bytes and DMA would make sure FIFO is almost always full therefore improving FIFO occupancy in both master and slave mode. Signed-off-by: Vignesh R <vigneshr@ti.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-10-19spi: omap2-mcspi: Switch to readl_poll_timeout()Vignesh R
Use standard readl_poll_timeout() macro for polling on status bits. Signed-off-by: Vignesh R <vigneshr@ti.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-07-30spi: omap2-mcspi: remove several redundant variablesColin Ian King
Variable count, l, mcspi and spi_cntrl are being assigned but are never used hence they are redundant and can be removed. Cleans up clang warnings: warning: variable 'count' set but not used [-Wunused-but-set-variable] warning: variable 'l' set but not used [-Wunused-but-set-variable] warning: variable 'mcspi' set but not used [-Wunused-but-set-variable] warning: variable 'spi_cntrl' set but not used [-Wunused-but-set-variable] Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-05-21spi: omap2-mcspi: Remove unnecessary pm_runtime_force_suspend()Tony Lindgren
Commit 5a686b2c9ed4 ("spi: omap2-mcspi: Idle hardware during suspend and resume") added calls for pm_runtime_force_suspend() and pm_runtime_force_resume() to make sure spi is idled between device_prepare() and device_complete(). But testing Linux next, I now noticed that we will get the following: spi_master spi0: Failed to power device: -13 Looking at things more turns out we can just remove this non-standard code. I was probably testing with some extra experimental patches earlier when I thought we need pm_runtime_force_suspend() and pm_runtime_force_resume(). Fixes: 5a686b2c9ed4 ("spi: omap2-mcspi: Idle hardware during suspend and resume") Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-05-02spi: omap2-mcspi: Idle hardware during suspend and resumeTony Lindgren
We currently are calling mcspi suspend and resume without considering that mcspi might provide resources for other device driver such as regulators. This means resume can fail and will produce -EACCES if errors if anything calls mcspi functions between device_prepare() and device_complete(). To fix the issue, let's do the following changes: 1. Let's add checking for return values for pm_runtime_get calls, and call pm_runtime_put_noidle() on errors. Things still fail after this change, but at least we see something is wrong as we now see -EACCES errors on resume. 2. Let's use noirq level for suspend and resume as other drivers can still call SPI related functions on suspend and resume. This still won't fix the -EACCES issue, but gets us to something a bit saner. 3. Finally, let's modify suspend and resume to call to make sure the device is idled properly on suspend. We have device_prepare() call pm_runtime_get_noresume() that won't get released until in device_complete() when it calls pm_runtime_put(). So if SPI is still active on entering suspend, it will never get idled unless we add calls to pm_runtime_force_suspend() and resume. This also fixes the -EACCES errors on resume together with changes 1 and 2 above. And since we're already rewriting suspend resume functions, let's arrange the order of suspend and resume functions to be like they usually are with suspend first. Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2018-05-02spi: omap2-mcspi: Restore context always in runtime_resumeTony Lindgren
We can have the SoC enter off mode also during idle, not just during suspend. Currently we are handling the CS restore properly for unused CS only for resume and not for runtime resume. Let's just move all the context related restore to runtime_resume(). Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-08-18spi: omap: Allocate bus number from spi frameworkSuniel Mahesh
spi framework should allocate bus number dynamically either via Linux IDR or spi alias for master drivers. This patch deletes code pertaining to manual allocation of spi bus number in spi omap2 master driver. Signed-off-by: Suniel Mahesh <sunil.m@techveda.org> Signed-off-by: Karthik Tummala <karthik@techveda.org> Tested-by: Karthik Tummala <karthik@techveda.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-05-26spi: omap2-mcspi: remove redundant check for error statusColin Ian King
The check to see if status is less than zero is actually redundant as all previous places where it is -ve have already branched to the exit paths, so it is never less than zero at the check. Detected by CoverityScan, CID#1357119 ("Logically dead code") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2017-03-24spi: omap2-mcspi: poll OMAP2_MCSPI_CHSTAT_RXS for PIO transferAkinobu Mita
When running the spi-loopback-test with slower clock rate like 10 KHz, the test for 251 bytes transfer was failed. This failure triggered an spi-omap2-mcspi's error message "DMA RX last word empty". This message means that PIO for reading the remaining bytes due to the DMA transfer length reduction is failed. This problem can be fixed by polling OMAP2_MCSPI_CHSTAT_RXS bit in channel status register to wait until the receive buffer register is filled. Cc: Mark Brown <broonie@kernel.org> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-10-24spi: omap2-mcspi: Remove redundant return value check of platform_get_resource()Wei Yongjun
Remove unneeded error handling on the result of a call to platform_get_resource() when the value is passed to devm_ioremap_resource(). Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-10-21spi: omap2-mcspi: Fix modifying platform resource dataVikram N
currently during probe the resource data gets modified and device physical address remains valid only during first load. If the module is unloaded and loaded again, the ioremp will be done on a incorrect address as the resource was modified during previous module load. This patch fixes this issue. Signed-off-by: Vikram N <vicky773@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-07-08spi: omap2-mcspi: Use the SPI framework to handle DMA mappingFranklin S Cooper Jr
Currently, the driver handles mapping buffers to be used by the DMA. However, there are times that the current mapping implementation will fail for certain buffers. Fortunately, the SPI framework can detect and map buffers so its usable by the DMA. Update the driver to utilize the SPI framework for buffer mapping instead. Also incorporate hooks that the framework uses to determine if the DMA can or can not be used. This will result in the original omap2_mcspi_transfer_one function being deleted and omap2_mcspi_work_one being renamed to omap2_mcspi_transfer_one. Previously transfer_one was only responsible for mapping and work_one handled the transfer. But now only transferring needs to be handled by the driver. Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-07-05spi: omap2-mcspi: Add comments for RX only DMA buffer workaroundFranklin S Cooper Jr
OMAP35x and OMAP37x mentions in the McSPI End-of-Transfer Sequences section that if the McSPI is configured as a Master and only DMA RX is being performed then the DMA transfer size needs to be reduced by 1 or 2. This was originally implemented by: commit 57c5c28dbc83 ("spi: omap2_mcspi rxdma bugfix") This patch adds comments to clarify what is going on in the code since its not obvious what problem its addressing. Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com> Signed-off-by: Mark Brown <broonie@kernel.org>